COMMENT:
EHJ notes that Śukra and Bṛhaspati are regularly coupled together as the authors of the first treatises on political science.

The first point to emphasize, again, is that this bunch of Brahmans was concerned in the first instance with religious concerns – the division into secular vs sacred, and a subjective view of the universe in which the moon is naturally the best of planets. But now the bunch of Brahmans is concerning itself with causality and in this verse with political science. Later we will encounter an individual Brahman who is not one of the bunch, Asita by name.

Coming back to today's verse, I think Aśvaghoṣa's intention is that each reader should find for himself or herself the faults in the Brahmans' argument, which can be challenged on many levels.

For a start, in their attempts to find justification in precedents in ancient Indian legends, the Brahmans are saying something here that is reminiscent of what Nanda says to himself in Saundarananda Canto 7, the gist of which is “My attempt to live the celibate life of one who has gone forth is doomed to failure. The thought that I could ever do it was sheer optimism. Just look at the objective facts of history -- Overcome by desire, the fire god 'Golden Sperm,' succumbed to sex with his wife Svāhā, as did Indra with nymph Ahalyā....” and so on, and so on.

One definition of the FM Alexander Technique that my Alexander head of training Ray Evans used to like was “Observing what is, and allowing what can be.”

Aśvaghoṣa's implied criticism of the Brahmans in the series of verses which is now beginning, as also his implied criticism of Nanda in SN Canto 7, might be that efforts to observe what is, on their own, are as dry as dust. All the drier are efforts to observe what has (allegedly) been – unless those efforts are ultimately directed at allowing what can be.

In the end, all the pessimistic thoughts which Nanda expressed in Canto 7, backed up as they were like a good Ph. D. thesis with plentiful references to the literature, were totally unfounded. Nanda did not know what was possible, nor could he know, nor can any scientist ever know what might be possible. Probably not even the Buddha knew what might be possible for Nanda. (Hence: 'When shall I see Nanda settled, given over to the living of a forest beggar's life?', / So thinking, I had harboured from the start the desire to see you thus. What a wonderful sight you are for me to behold! // 18.33 // ) But both the Buddha and Ānanda knew what direction to point Nanda in, having gone that way themselves.

Just as Nanda's plentiful references to precedent were proved by subsequent developments to be meaningless, meaningless also will the argument be shown to be which the Brahmans are about to make, backed though it is by plentiful references to historical precedents in the Brahamanical literature.

The argument itself, as presented in today's verse, is that founders of a lineage cannot clarify everything that is to be clarified; rather, they set the ball rolling and leave their descendants, using their own creativity, to carry on a process akin to biological evolution.

Contrast this argument to what the Buddha tells Nanda, for example, in SN16.43:

“Though your head and clothes be on fire direct your mind so as to be awake to the truths.”

Our fundamental aim, then, is not to gain a Ph. D., or a Nobel Prize, by clarifying something that has not hitherto been clarified, as if opening up a new channel, or nurturing a new twig. Our fundamental aim is rather to get back to the source, to dig down to the root, to clarify what the Buddha clarified, by directing the mind so as to be awake to the Buddha's four noble truths.

This assertion sounds preachy and religious, but I think it rests not on belief but rather on integrity. If one claims to be teaching the FM Alexander Technique, integrity lies in being interested in what FM Alexander actually taught and in endeavouring to make that teaching one's own. Religious belief does not come into it. Similarly if one purports to be following the teaching of the Buddha, the task is not to be creative with the Buddha's teaching. The task, primarily, is just to sit, learning the backward step of turning one's own light and letting it shine.

VOCABULARY
yad (relative pronoun): [that] which
rāja-śāstram (acc. sg.): science of kingship
rājan: m. king
śāstra: n. an order , command , precept , rule ; teaching , instruction , direction ; any instrument of teaching , any manual or compendium of rules , any bock or treatise , (esp.) any religious or scientific treatise , any sacred book or composition of divine authority ; (the word śāstra is often found ifc. after the word denoting the subject of the book , or is applied collectively to whole departments of knowledge)
bhṛguḥ (nom. sg.): m. sg. N. of a ṛṣi regarded as the ancestor of the bhṛgus (he has the patr.vāruṇi and is the supposed author of RV. ix , 65 ; x , 19 ; he is enumerated among the 10 maharṣis created by the first manu)
aṅgirā (nom. sg.): m. N. of a ṛṣi , author of the hymns of RV. ix, of a code of laws , and of a treatise on astronomy
vā: or
na: not

kālena: ind. instr. in the course of time
śukraḥ (nom. sg. ): m. “bright, resplendent,” the planet Venus or its regent (regarded as the son of bhṛgu and preceptor of the daityas)
ca: and
bṛhas-pati (nom. sg.): m. "lord of prayer or devotion " N. of a deity (in whom Piety and Religion are personified ; he is the chief offerer of prayers and sacrifices , and therefore represented as the type of the priestly order , and the purohita of the gods with whom he intercedes for men ; in later times he is the god of wisdom and eloquence , to whom various works are ascribed ; he is also regarded as son of aṅgiras , husband of tārā and father of kaca , and sometimes identified with vyāsa ; in astronomy he is the regent of Jupiter and often identified with that planet)
ca: and